Serena Williams may be a 23-time grand slam champion, but she had a day to forget when she was thrashed 6-1 6-0 by Johanna Konta.
Williams, who reached the Wimbledon final last month, said she had "so many things on my mind" after being stunned by the Briton at the Silicon Valley Classic in San Jose on Tuesday.
Even at 36, Williams rarely experiences defeat on the WTA Tour and this was the most lopsided loss of her entire career.
Here we take a look at five of the heaviest defeats Williams has suffered.
IGA Tennis Classic (1998) - Joannette Kruger (6-1 6-1)
Williams was just 16-years-old and playing in only the ninth tournament of her career when she was handed a lesson by South African Joannette Kruger in Oklahoma City.
US Open (2011) - Sam Stosur (6-2 6-3)
Australian Sam Stosur was a huge underdog in the US Open final but managed to secure an upset victory over Williams, who vented her fury at the umpire. The unimpressed American yelled: "You're out of control" and "You're a hater, and you're just unattractive inside" in an ugly tirade after a contentious point was awarded to Stosur.
French Open (2014) - Garbine Muguruza (6-2 6-2)
The defending champion at Roland Garros, Williams was a second-round casualty against an opponent competing in just her sixth grand slam. It marked the first time Williams had failed to reach the second week of a grand slam being the top seed.
WTA Finals (2014) - Simona Halep (6-0 6-2)
Later in 2014, Williams suffered an even bigger defeat against an opponent in the form of Simona Halep who had only won one set against her in their previous three meetings. It was only the eighth occasion in which she had suffered a bagelling in a set. Halep had shown her burgeoning talent by reaching the final of the French Open in the same year.
Silicon Valley Classic (2018) - Johanna Konta (6-1 6-0)
Two decades on from being battered by Kruger, Williams was stunned by Konta as she lost a dozen games in a row. The American great had defied the odds to reach the final of Wimbledon last month despite only giving birth to her first child last September, but was out of sorts against the inspired Briton.